With the efficacy of implantable cardioverter defibrillator(ICD)therapy well established, it is important to understand how ICD recipients perceive their dependence on this life saving technology and how these perceptions influence their health-related quality of life (HRQL). The purpose of this study is to test a theoretical model that may explain the link between attitudes towards dependency on technology and HRQL in a sample of adult ICD recipients. The model consists of seven variables: attitudes towards technology dependency; age; gender; illness history; illness representation; symptom distress; and HRQL. Adult subjects who have received an ICD will complete a mailed questionnaire measuring HRQL,illness perceptions,and symptom distress. Data collection is complete. Structural Equation Modeling techniques will be used to analyze data.